CVE-2021-29961: Medium severity Mozilla Firefox vulnerability

Published Jun 1, 2021
·
Updated

When styling and rendering an oversized <select> element, Firefox did not apply correct clipping which allowed an attacker to paint over the user interface.

Other sources

When styling and rendering an oversized <select> element, Firefox did not apply correct clipping which allowed an attacker to paint over the user interface. This vulnerability affects Firefox < 89.

When styling and rendering an oversized <select> element, Firefox did not apply correct clipping which allowed an attacker to paint over the user interface.

Affected Software

17 affected componentsFixes available
Mozilla Firefox<89
89
Mozilla Firefox>=78.11.0<89.0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 89
  2. Upgrade

    Upgrade alpine/firefox to a version that resolves this vulnerability.

    Fixed in 89.0-r0
  3. Upgrade

    Upgrade alpine/librewolf to a version that resolves this vulnerability.

    Fixed in 89.0-r0

Event History

Jun 1, 2021
CVE Published
12:00 AM
Jun 24, 2021
CVE Published
via MITRE·01:15 PM
Data Sourced
via MITRE·01:15 PM
DescriptionWeakness
Data Sourced
via NVD·02:15 PM
DescriptionSeverityWeaknessAffected Software
Data Sourced
via OSV·02:15 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is the vulnerability ID?

The vulnerability ID is CVE-2021-29961.

2

What is the title of the vulnerability?

The title of the vulnerability is 'When styling and rendering an oversized <select> element Firefox did not apply correct clipping which allowed an attacker to paint over the user interface.'

3

What is the affected software?

The affected software is Mozilla Firefox version up to exclusive version 89.

4

What is the severity of the vulnerability?

The severity of the vulnerability is medium.

5

How can I fix the vulnerability?

To fix the vulnerability, update your Mozilla Firefox browser to version 89 or later.

Company

Resources

Contact

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